CYSTOPTEEIS DIPLAZIUM HYMENOPHYLLUM. 181 



Dickieana has shorter fronds, with the pinnae crowded 

 together. 



C. MONTANA (Mountain). This is also a native of our 

 own country; and, like many other alpine plants, is rather 

 difficult to manage. It has triangular, bipinnate fronds ; the 

 rhizomes creeping. It should be kept moist while growing 

 freely. It may be more safely grown in a frame, and therefore 

 duplicates only should be trusted on the open fernery. 



C. SEMPEEVIEENS (Evergreen). Unlike the last-named 

 plant, this Fern keeps its fronds nearly perfect all winter. 

 Mr. Moore thinks it is only a variety of C. fragilis. 



C. TENUIS is described among the Greenhouse Ferns, and, 

 like the last, it is only safe there ; though if there be a plant 

 to spare, it may be tried out of doors. 



DIPLAZIUM. 



DIPLAZIUM THELYPTEKOIDES (Thelypteris-like). This Fern 

 is from North America, and is .the only one of the genus which 

 is hardy. The fronds are lanceolate, 2 feet high, twice-divided, 

 hairy below, with thick creeping rhizome and scaly stalks. It 

 is very distinct, and well worth a place in the fernery. 



HYMENOPHYLLUM. 



A genus of very delicate Ferns, containing only two species 

 which are indigenous to Britain. The name is derived from 

 hymen, a membrane, and pteron, a leaf. 



HYMENOPHYLLUM TTJNERIDGENSE (Tunbridge Fern). So 

 named because it was formerly found there in great quantity, 

 and that locality was supposed to be the only one where it 

 grew ; but it has been found in the hill districts of Yorkshire, 

 and is so plentiful in Ireland, that we have received a large 

 batch of TricJwmanes radicans from thence, packed in large 

 patches of Hymenophyllum. Fronds pinnate, from 1 to 4 inches 



